taint, tainter means: The small flap of skin on males that's tucked behind the scrotum and in front of the anus. Origin from "it ain't". "'Taint quite yer balls and 'taint quite yer asshole". Basically the area of skin between the genitals and the anus e.g. "t'ain't 'zactly the scrote, t'ain't 'zactly the asshole"